Feeding highly active phosphinimine catalysts to a gas phase reactor

Abstract

A highly active, supported phosphinimine catalyst is fed to a gas phase reactor as a slurry in a liquid hydrocarbon. Feeding the catalyst to a gas phase reactor in a viscous liquid hydrocarbon modifies catalyst initiation kinetics.

What is claimed is: 
     
       1. A polymerization process comprising:
 introducing ethylene and at least one alpha olefin to a gas-phase reactor; 
 introducing a catalyst slurry comprising a supported polymerization catalyst and a mineral oil to the reactor; and 
 polymerizing the ethylene and the at least one alpha olefin in the presence of the supported polymerization catalyst; 
 wherein said supported polymerization catalyst comprises: i) a phosphinimine catalyst having the formula ((R*)(Ar—F)C 5 H 3 )Ti(N═P(t-Bu) 3 )X 2 ; 
 where R* is hydrogen or a hydrocarbyl group, Ar—F is a perfluorinated aryl group, a 2,6 fluoro substituted phenyl group, a 2,4,6 fluoro substituted phenyl group, or a 2,3,5,6 fluoro substituted phenyl group; and X is an activatable ligand; ii) a cocatalyst, and iii) an inert support. 
 
     
     
       2. The process of  claim 1  wherein the phosphinimine catalyst has the formula (1,2-(R*)(Ar—F)C 5 H 3 )Ti(N═P(t-Bu) 3 )X 2 ; where R* is a hydrocarbyl group having from 1 to20 carbon atoms; Ar—F is a perfluorinated aryl group, a 2,6 fluoro substituted phenyl group,a 2,4,6 fluoro substituted phenyl group, or a 2,3,5,6 fluoro substituted phenyl group; and X is an activatable ligand. 
     
     
       3. The process of  claim 1  wherein the phosphinimine catalyst has the formula ((Ar—F)Cp)Ti(N═P(t-Bu) 3 )X 2 ; where Ar—F is a perfluorinated aryl group, a 2,6 fluoro substituted phenyl group, a 2,4,6 fluoro substituted phenyl group, or a 2,3,5,6 fluoro substituted phenyl group; and X is an activatable ligand. 
     
     
       4. The process of  claim 1  wherein the mineral oil makes up at least 75 wt % of the entire weight of the catalyst slurry. 
     
     
       5. The process of  claim 1  wherein the gas phase reactor is a fluidized bed reactor. 
     
     
       6. A method for increasing the induction period of a supported polymerization catalyst in a gas phase polymerization process, the method comprising:
 combining the supported polymerization catalyst with mineral oil to give a catalyst slurry; and 
 introducing the catalyst slurry to a gas phase reactor to polymerize ethylene and at least one alpha olefin;
 wherein the supported polymerization catalyst comprises: i) a phosphinimine catalyst having the formula ((R*)(Ar—F)C 5 H 3 )Ti(N═P(t-Bu) 3 )X 2 ; where R* is hydrogen or a hydrocarbyl group; Ar—F is a perfluorinated aryl group, a 2,6 fluoro substituted phenyl group, a 2,4,6 fluoro substituted phenyl group, or a 2,3,5,6 fluoro substituted phenyl group; and X is an activatable ligand; ii) a cocatalyst, and iii) an inert support. 
 
 
     
     
       7. The method of  claim 6  wherein the phosphinimine catalyst has the formula (1,2-(R*)(Ar—F)C 5 H 3 )Ti(N═P(t-Bu) 3 )X 2 ; where R* is a hydrocarbyl group having from 1 to 20 carbon atoms; Ar—F is a perfluorinated aryl group, a 2,6 fluoro substituted phenyl group, a 2,4,6 fluoro substituted phenyl group, or a 2,3,5,6 fluoro substituted phenyl group; and X is an activatable ligand. 
     
     
       8. The method of  claim 6  wherein the phosphinimine catalyst has the formula ((Ar—F)Cp)Ti(N═P(t-Bu) 3 )X 2 ; where Ar—F is a perfluorinated aryl group, a 2,6 fluoro substituted phenyl group, a 2,4,6 fluoro substituted phenyl group, or a 2,3,5,6 fluoro substituted phenyl group; and X is an activatable ligand. 
     
     
       9. The method of  claim 6  wherein the mineral oil makes up at least 75 wt % of the entire weight of the catalyst slurry.